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1.
Cell ; 136(1): 85-96, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-19135891

RESUMO

Condensins are key mediators of chromosome condensation across organisms. Like other condensins, the bacterial MukBEF condensin complex consists of an SMC family protein dimer containing two ATPase head domains, MukB, and two interacting subunits, MukE and MukF. We report complete structural views of the intersubunit interactions of this condensin along with ensuing studies that reveal a role for the ATPase activity of MukB. MukE and MukF together form an elongated dimeric frame, and MukF's C-terminal winged-helix domains (C-WHDs) bind MukB heads to constitute closed ring-like structures. Surprisingly, one of the two bound C-WHDs is forced to detach upon ATP-mediated engagement of MukB heads. This detachment reaction depends on the linker segment preceding the C-WHD, and mutations on the linker restrict cell growth. Thus ATP-dependent transient disruption of the MukB-MukF interaction, which creates openings in condensin ring structures, is likely to be a critical feature of the functional mechanism of condensins.


Assuntos
Adenosina Trifosfatases/química , Bactérias/química , Proteínas de Bactérias/química , Proteínas de Ligação a DNA/química , Complexos Multiproteicos/química , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Sítios de Ligação , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Modelos Moleculares , Complexos Multiproteicos/metabolismo , Estrutura Terciária de Proteína
2.
Lab Invest ; 103(8): 100159, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37088465

RESUMO

Central neurocytoma (CN) is a low-grade neuronal tumor that mainly arises from the lateral ventricle (LV). This tumor remains poorly understood in the sense that no driver gene aberrations have been identified thus far. We investigated immunomarkers in fetal and adult brains and 45 supratentorial periventricular tumors to characterize the biomarkers, cell of origin, and tumorigenesis of CN. All CNs occurred in the LV. A minority involved the third ventricle, but none involved the fourth ventricle. As expected, next-generation sequencing performed using a brain-tumor-targeted gene panel in 7 CNs and whole exome sequencing in 5 CNs showed no driver mutations. Immunohistochemically, CNs were robustly positive for FGFR3 (100%), SSTR2 (92%), TTF-1 (Nkx2.1) (88%), GLUT-1 (84%), and L1CAM (76%), in addition to the well-known markers of CN, synaptophysin (100%) and NeuN (96%). TTF-1 was also positive in subependymal giant cell astrocytomas (100%, 5/5) and the pituicyte tumor family, including pituicytoma and spindle cell oncocytoma (100%, 5/5). Interestingly, 1 case of LV subependymoma (20%, 1/5) was positive for TTF-1, but all LV ependymomas were negative (0/5 positive). Because TTF-1-positive cells were detected in the medial ganglionic eminence around the foramen of Monro of the fetal brain and in the subventricular zone of the LV of the adult brain, CN may arise from subventricular TTF-1-positive cells undergoing neuronal differentiation. H3K27me3 loss was observed in all CNs and one case (20%) of LV subependymoma, suggesting that chromatin remodeling complexes or epigenetic alterations may be involved in the tumorigenesis of all CNs and some ST-subependymomas. Further studies are required to determine the exact tumorigenic mechanism of CN.


Assuntos
Glioma Subependimal , Neurocitoma , Humanos , Neurocitoma/genética , Neurocitoma/patologia , Histonas/genética , Epigênese Genética , Carcinogênese
3.
J Korean Med Sci ; 38(43): e356, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37935168

RESUMO

The goal of the methylation classifier in brain tumor classification is to accurately classify tumors based on their methylation profiles. Accurate brain tumor diagnosis is the first step for healthcare professionals to predict tumor prognosis and establish personalized treatment plans for patients. The methylation classifier can be used to perform classification on tumor samples with diagnostic difficulties due to ambiguous histology or mismatch between histopathology and molecular signatures, i.e., not otherwise specified (NOS) cases or not elsewhere classified (NEC) cases, aiding in pathological decision-making. Here, the authors elucidate upon the application of a methylation classifier as a tool to mitigate the inherent complexities associated with the pathological evaluation of brain tumors, even when pathologists are experts in histopathological diagnosis and have access to enough molecular genetic information. Also, it should be emphasized that methylome cannot classify all types of brain tumors, and it often produces erroneous matches even with high matching scores, so, excessive trust is prohibited. The primary issue is the considerable difficulty in obtaining reference data regarding the methylation profile of each type of brain tumor. This challenge is further amplified when dealing with recently identified novel types or subtypes of brain tumors, as such data are not readily accessible through open databases or authors of publications. An additional obstacle arises from the fact that methylation classifiers are primarily research-based, leading to the unavailability of charging patients. It is important to note that the application of methylation classifiers may require specialized laboratory techniques and expertise in DNA methylation analysis.


Assuntos
Neoplasias Encefálicas , Metilação de DNA , Humanos , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Prognóstico , Bases de Dados Factuais
4.
Lab Invest ; 102(2): 160-171, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34848827

RESUMO

Mismatch repair-deficient (MMRD) brain tumors are rare among primary brain tumors and can be induced by germline or sporadic mutations. Here, we report 13 MMRD-associated (9 sporadic and 4 Lynch syndrome) primary brain tumors to determine clinicopathological and molecular characteristics and biological behavior. Our 13 MMRD brain tumors included glioblastoma (GBM) IDH-wildtype (n = 9) including 1 gliosarcoma, astrocytoma IDH-mutant WHO grade 4 (n = 2), diffuse midline glioma (DMG) H3 K27M-mutant (n = 1), and pleomorphic xanthoastrocytoma (PXA) (n = 1). Next-generation sequencing using a brain tumor-targeted gene panel, microsatellite instability (MSI) testing, Sanger sequencing for germline MMR gene mutation, immunohistochemistry of MMR proteins, and clinicopathological and survival analysis were performed. There were many accompanying mutations, suggesting a high tumor mutational burden (TMB) in 77%, but TMB was absent in one case of GBM, IDH-wildtype, DMG, and PXA, respectively. MSH2, MLH1, MSH6, and PMS2 mutations were found in 31%, 31%, 31% and 7% of patients, respectively. MSI-high and MSI-low were found in 50% and 8% of these gliomas, respectively and 34% was MSI-stable. All Lynch syndrome-associated GBMs had MSI-high. In addition, 77% (10/13) had histopathologically multinucleated giant cells. The progression-free survival tended to be poorer than the patients with no MMRD gliomas, but the number and follow-up duration of our patients were insufficient to get statistical significance. In the present study, we found that the most common MMRD primary brain tumor was GBM IDH-wildtype. The genetic profile of MMRD GBM was different from that of conventional GBM. MMRD gliomas with TMB and MSI-H may be sensitive to immunotherapy but resistant to temozolomide. Our findings can help develop better treatment options.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Encéfalo/metabolismo , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Mutação , Adolescente , Adulto , Idoso , Antineoplásicos Alquilantes/uso terapêutico , Biomarcadores Tumorais/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Criança , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Linhagem , Temozolomida/uso terapêutico
5.
J Korean Med Sci ; 36(50): e344, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34962116

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic is being overcome by widespread inoculation with various COVID-19 vaccines, but concerns about the safety of the vaccines are a major hurdle to widespread vaccination. We report the first case of adult-onset Still's disease (AOSD) developing in a 36-year-old, previously healthy woman after the first dose of BNT162b2 mRNA COVID-19 vaccine (Pfizer). She visited our hospital due to high spiking fever and sore throat that developed 10 days after vaccination. Based on thorough investigations and changes in symptoms and signs after admission, she was diagnosed with AOSD and treated with high dose steroids and tocilizumab. This report suggests the possibility that AOSD could be triggered by COVID-19 vaccines through activation of the innate immune system.


Assuntos
Vacina BNT162/efeitos adversos , Doença de Still de Início Tardio/etiologia , Vacinação/efeitos adversos , Adulto , Feminino , Humanos , Imunidade Inata , Doença de Still de Início Tardio/tratamento farmacológico
6.
Clin Exp Rheumatol ; 34(6 Suppl 102): S64-S71, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27462914

RESUMO

OBJECTIVES: To evaluate the efficacy of tocilizumab (TCZ), a monoclonal antibody against the interleukin (IL)-6 receptor, for refractory adult-onset Still's disease (AOSD) in the Korean population. METHODS: This retrospective study included 22 Korean patients with refractory AOSD who were given TCZ at one of seven university hospital-based clinics for rheumatic disease. Patients were subdivided into groups according to disease course: monocyclic, systemic polycyclic, and chronic articular. Modified Pouchot scores, including laboratory and clinical findings, were analysed at 6 months and 12 months. RESULTS: TCZ was given at 4-8 mg/kg every 4-5 weeks (8 mg/kg every 4-5 weeks in 18 patients, 6 mg/kg every 4 weeks in 2, and 4 mg/kg every 4 weeks in 2) for 7.5 months (median, IQR: 4.0-12.3). A good response (measured as a decrease of >2 in the modified Pouchot score) was achieved in 50.0% of patients (11 of 22) at 6 months and in 64.3% (9 of 14) at 12 months. The dose of corticosteroid dose was reduced from 11.5 mg/day (median, IQR: 10.0-21.3) immediately before TCZ therapy to 7.5 mg/day (median, IQR: 5.0-10.0, p=0.002) at 6 months and finally to 6.3 mg/day (median, IQR: 5.0-7.5, p=0.002) at 12 months. Only one patient discontinued TCZ treatment due to facial swelling accompanied by high blood pressure. In all others, adverse events subsided with delayed TCZ therapy, and TCZ therapy was continued successfully without problems. CONCLUSIONS: TCZ was effective for treating Korean AOSD patients who were refractory to conventional therapy or other anti-cytokine biologics, showing a corticosteroid-sparing effect and an acceptable tolerance profile.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/uso terapêutico , Doença de Still de Início Tardio/tratamento farmacológico , Corticosteroides/administração & dosagem , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Estudos Retrospectivos , Doença de Still de Início Tardio/sangue , Doença de Still de Início Tardio/diagnóstico , Fatores de Tempo , Resultado do Tratamento
7.
J Allergy Clin Immunol ; 136(5): 1254-64, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26428954

RESUMO

BACKGROUND: Atopic dermatitis (AD) shows very high prevalence in Asia, with a large unmet need for effective therapeutics. Direct comparisons between European American (EA) and Asian patients with AD are unavailable, but earlier blood studies detected increased IL-17(+)-producing cell counts in Asian patients with AD. OBJECTIVE: We sought to characterize the Asian AD skin phenotype and compare it with the EA AD skin phenotype. METHODS: We performed genomic profiling (real-time PCR) and immunohistochemistry on lesional and nonlesional biopsy specimens from 52 patients with AD (25 EAs and 27 Asians), 10 patients with psoriasis (all EAs), and 27 healthy subjects (12 EAs and 15 Asians). RESULTS: Although disease severity/SCORAD scores were similar between the AD groups (58.0 vs 56.7, P = .77), greater acanthosis, higher Ki67 counts, and frequent parakeratosis were characteristics of lesional epidermis from Asian patients with AD (P < .05). Most (24/27) Asian patients had high IgE levels. A principal component analysis using real-time PCR data clustered the Asian AD phenotype between the EA AD and psoriasis phenotypes. TH2 skewing characterized both Asian and EA patients with AD but not patients with psoriasis. Significantly higher TH17 and TH22 (IL17A, IL19, and S100A12 in lesional and IL-22 in nonlesional skin; P < .05) and lower TH1/interferon (CXCL9, CXCL10, MX1, and IFNG in nonlesional skin; P < .05) gene induction typified AD skin in Asian patients. CONCLUSION: The Asian AD phenotype presents (even in the presence of increased IgE levels) a blended phenotype between that of EA patients with AD and those with psoriasis, including increased hyperplasia, parakeratosis, higher TH17 activation, and a strong TH2 component. The relative pathogenic contributions of the TH17 and TH2 axes in creating the Asian AD phenotype need to be tested in future clinical trials with appropriate targeted therapeutics.


Assuntos
Dermatite Atópica/etnologia , Dermatite Atópica/imunologia , Psoríase/etnologia , Psoríase/imunologia , Células Th17/imunologia , Adolescente , Adulto , Idoso , Povo Asiático , Diferenciação Celular , Citocinas/metabolismo , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Fenótipo , Análise de Componente Principal , Pele/imunologia , Pele/patologia , Células Th2/imunologia , População Branca , Adulto Jovem
8.
J Biol Chem ; 289(45): 31330-40, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25237190

RESUMO

Angiopoietin-2 (Ang-2) not only regulates angiogenesis by binding to its well known receptor Tie2 on endothelial cells but also controls sprouting of Tie2-negative angiogenic endothelial cells and invasion of Tie2-negative non-endothelial cells by binding to integrins. However, the molecular mechanism of the Ang-2/integrin association has been unclear. In this study, we found that the Gln-362 residue of Ang-2 was essential for binding to α5ß1 integrin. A Q362E Ang-2 mutant, which still bound to Tie2, failed to associate with α5ß1 integrin and was unable to activate the integrin downstream signaling of focal adhesion kinase. In addition, unlike wild-type Ang-2, the Q362E Ang-2 mutant was defective in mediating invasion of Tie2-negative glioma or Tie2-positive endothelial cells. Furthermore, the tailpiece domain of the α5 subunit in α5ß1 integrin was critical for binding to Ang-2. Taken together, these results provide a novel insight into the mechanism of integrin regulation by Ang-2, which contributes to tumor invasion and endothelial cell migration in a Tie2-independent manner.


Assuntos
Angiopoietina-2/metabolismo , Células Endoteliais/citologia , Glutamina/metabolismo , Integrina alfa5beta1/metabolismo , Neoplasias/metabolismo , Receptor TIE-2/metabolismo , Animais , Células CHO , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Cricetinae , Cricetulus , Regulação da Expressão Gênica , Humanos , Integrinas/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/patologia , Neovascularização Patológica , Plasmídeos/metabolismo , Estrutura Terciária de Proteína
9.
J Korean Med Sci ; 30(6): 700-4, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26028920

RESUMO

Septic arthritis and gout are major diseases that should be suspected in patients with acute monoarthritis. These two diseases are clinically similar and often indistinguishable without the help of synovial fluid analysis. Recently, a novel diagnostic rule for gout without synovial fluid analysis was developed and showed relevant performances. This study aimed to determine whether this diagnostic rule could perform well in distinguishing gout from septic arthritis. The diagnostic rule comprises 7 clinical and laboratory variables, each of which is given a specified score. The probability of gout is classified into 3 groups according to the sum of the scores: high (≥ 8), intermediate (> 4 to < 8) and low probability (≤ 4). In this retrospective study, we applied this diagnostic rule to 136 patients who presented as acute monoarthritis and were subsequently diagnosed as acute gout (n = 82) and septic arthritis (n = 54) based on synovial fluid analysis. The mean sum of scores of acute gout patients was significantly higher than that of those with septic arthritis (8.6 ± 0.2 vs. 3.6 ± 0.32, P < 0.001). Patients with acute gout had significantly more 'high', and less 'low' probabilities compared to those with septic arthritis (Eta[η]: 0.776). The prevalence of acute gouty arthritis, as confirmed by the presence of monosodium crystal, was 95.5% (61/64), 57.5% (19/33), and 5.1% (2/39) in high, intermediate and low probability group, respectively. The recently introduced diagnostic rule properly discriminates acute gout from septic arthritis. It may help physicians diagnose gout in cases difficult to be differentiated from septic arthritis.


Assuntos
Algoritmos , Artrite Gotosa/diagnóstico , Artrite Infecciosa/diagnóstico , Interpretação Estatística de Dados , Técnicas de Apoio para a Decisão , Diagnóstico por Computador/métodos , Doença Aguda , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
EMBO J ; 29(2): 496-504, 2010 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-19942850

RESUMO

GDP-bound prenylated Rabs, sequestered by GDI (GDP dissociation inhibitor) in the cytosol, are delivered to destined sub-cellular compartment and subsequently activated by GEFs (guanine nucleotide exchange factors) catalysing GDP-to-GTP exchange. The dissociation of GDI from Rabs is believed to require a GDF (GDI displacement factor). Only two RabGDFs, human PRA-1 and Legionella pneumophila SidM/DrrA, have been identified so far and the molecular mechanism of GDF is elusive. Here, we present the structure of a SidM/DrrA fragment possessing dual GEF and GDF activity in complex with Rab1. SidM/DrrA reconfigures the Switch regions of the GTPase domain of Rab1, as eukaryotic GEFs do toward cognate Rabs. Structure-based mutational analyses show that the surface of SidM/DrrA, catalysing nucleotide exchange, is involved in GDI1 displacement from prenylated Rab1:GDP. In comparison with an eukaryotic GEF TRAPP I, this bacterial GEF/GDF exhibits high binding affinity for Rab1 with GDP retained at the active site, which appears as the key feature for the GDF activity of the protein.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/química , Inibidores de Dissociação do Nucleotídeo Guanina/metabolismo , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Legionella pneumophila/metabolismo , Doença dos Legionários/metabolismo , Proteínas rab1 de Ligação ao GTP/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Lipossomos/metabolismo , Magnésio/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Mutação Puntual , Ligação Proteica , Conformação Proteica , Alinhamento de Sequência , Especificidade por Substrato , Inibidores da Dissociação do Nucleotídeo Guanina rho-Específico
11.
PLoS Pathog ; 8(12): e1003082, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23271971

RESUMO

Upon phagocytosis, Legionella pneumophila translocates numerous effector proteins into host cells to perturb cellular metabolism and immunity, ultimately establishing intracellular survival and growth. VipD of L. pneumophila belongs to a family of bacterial effectors that contain the N-terminal lipase domain and the C-terminal domain with an unknown function. We report the crystal structure of VipD and show that its C-terminal domain robustly interferes with endosomal trafficking through tight and selective interactions with Rab5 and Rab22. This domain, which is not significantly similar to any known protein structure, potently interacts with the GTP-bound active form of the two Rabs by recognizing a hydrophobic triad conserved in Rabs. These interactions prevent Rab5 and Rab22 from binding to downstream effectors Rabaptin-5, Rabenosyn-5 and EEA1, consequently blocking endosomal trafficking and subsequent lysosomal degradation of endocytic materials in macrophage cells. Together, this work reveals endosomal trafficking as a target of L. pneumophila and delineates the underlying molecular mechanism.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Endossomos/metabolismo , Legionella pneumophila/metabolismo , Legionelose/metabolismo , Macrófagos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas rab5 de Ligação ao GTP/metabolismo , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Transporte Biológico/genética , Proteínas de Transporte/genética , Proteínas de Ligação a DNA , Endossomos/genética , Endossomos/microbiologia , Endossomos/patologia , Células HeLa , Humanos , Legionella pneumophila/química , Legionella pneumophila/genética , Legionelose/genética , Legionelose/patologia , Lisossomos/genética , Lisossomos/metabolismo , Lisossomos/microbiologia , Lisossomos/patologia , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Proteínas Nucleares/genética , Estrutura Terciária de Proteína , Proteínas de Ligação a RNA , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Proteínas rab5 de Ligação ao GTP/genética
12.
Nucleic Acids Res ; 40(6): 2724-33, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22127865

RESUMO

RIG-I is a cytosolic receptor for non-self RNA that mediates immune responses against viral infections through IFNα/ß production. In an attempt to identify novel tools that modulate IFNα/ß production, we used SELEX technology to screen RNA aptamers that specifically target RIG-I protein. Most of the selected RIG-I aptamers contained polyU motifs in the second half regions that played critical roles in the activation of RIG-I-mediated IFNß production. Unlike other known ligands, RIG-I aptamer bound and activated RIG-I in a 5'-triphosphate-independent manner. The helicase and RD domain of RIG-I were used for aptamer binding, but intact RIG-I protein was required to exert aptamer-mediated signaling activation. Furthermore, replication of NDV, VSV and influenza virus in infected host cells was efficiently blocked by pre- or post-treatment with RIG-I aptamer. Based on these data, we propose that RIG-I aptamer has strong potential to be an antiviral agent that specifically boosts the RIG-I-dependent signaling cascade.


Assuntos
Antivirais/farmacologia , Aptâmeros de Nucleotídeos/farmacologia , RNA Helicases DEAD-box/metabolismo , Antivirais/química , Aptâmeros de Nucleotídeos/química , Sequência de Bases , Linhagem Celular , Proteína DEAD-box 58 , Humanos , Interferon beta/biossíntese , Dados de Sequência Molecular , Poli U/química , Polifosfatos/química , RNA/química , Receptores Imunológicos , Técnica de Seleção de Aptâmeros , Transdução de Sinais/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
14.
Tissue Eng Regen Med ; 21(4): 587-594, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38451425

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) have been highlighted as a potent therapeutic option for conditions with excessive osteoclast activity such as systemic and local bone loss in rheumatic disease. In addition to their immunomodulatory functions, MSCs also directly suppress osteoclast differentiation and activation by secreting osteoprotegerin (OPG) and IL-10 but the underlying mechanisms are still to be clarified. Tumor necrosis factor-stimulated gene-6 (TSG-6) is a potent anti-inflammatory molecule that inhibits osteoclast activation and has been shown to mediate MSC's immunomodulatory functions. In this study, we aimed to determine whether adipose tissue-derived MSC (ADMSC) inhibits the differentiation from osteoclast precursors to mature osteoclasts through TSG-6. METHODS: Human ADMSCs were co-cultured with bone marrow-derived monocyte/macrophage (BMMs) from DBA/1J or B6 mouse in the presence of osteoclastogenic condition (M-CSF 10 ng/mL and RANKL 10 ng/mL). In some co-culture groups, ADMSCs were transfected with siRNA targeting TSG-6 or OPG to determine their role in osteoclastogenesis. Tartrate-resistant acid phosphatase (TRAP) activity in culture supernatant and mRNA expression of osteoclast markers were investigated. TRAP+ multinucleated cells and F-actin ring formation were counted. RESULTS: ADMSCs significantly inhibited osteoclast differentiation under osteoclastogenic conditions. Suppression of TSG-6 significantly reversed the inhibition of osteoclast differentiation in a degree similar to that of OPG based on TRAP activity, mRNA expression of osteoclast markers, and numbers of TRAP+ multinucleated cell and F-actin ring formation. CONCLUSION: This study demonstrated that ADMSCs inhibit osteoclast differentiation through TSG-6 under osteoclastogenic conditions.


Assuntos
Tecido Adiposo , Moléculas de Adesão Celular , Diferenciação Celular , Células-Tronco Mesenquimais , Osteoclastos , Osteoclastos/metabolismo , Osteoclastos/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Animais , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Camundongos , Moléculas de Adesão Celular/metabolismo , Osteoprotegerina/metabolismo , Técnicas de Cocultura , Camundongos Endogâmicos C57BL , Osteogênese/efeitos dos fármacos , Fosfatase Ácida Resistente a Tartarato/metabolismo , Macrófagos/metabolismo , Macrófagos/citologia
15.
Arthritis Res Ther ; 26(1): 25, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229205

RESUMO

Recent evidence highlights the role of low-grade synovial inflammation in the progression of osteoarthritis (OA). Inflamed synovium of OA joints detected by imaging modalities are associated with subsequent progression of OA. In this sense, detecting and quantifying synovitis of OA by imaging modalities may be valuable in predicting OA progressors as well as in improving our understanding of OA progression. Of the several imaging modalities, molecular imaging such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) has an advantage of visualizing the cellular or subcellular events of the tissues. Depending on the radiotracers used, molecular imaging method can potentially detect and visualize various aspects of synovial inflammation. This narrative review summarizes the recent progresses of imaging modalities in assessing inflammation and OA synovitis and focuses on novel radiotracers. Recent studies about imaging modalities including ultrasonography (US), magnetic resonance imaging (MRI), and molecular imaging that were used to detect and quantify inflammation and OA synovitis are summarized. Novel radiotracers specifically targeting the components of inflammation have been developed. These tracers may show promise in detecting inflamed synovium of OA and help in expanding our understanding of OA progression.


Assuntos
Osteoartrite , Sinovite , Humanos , Sinovite/diagnóstico por imagem , Osteoartrite/diagnóstico por imagem , Osteoartrite/complicações , Membrana Sinovial , Inflamação , Imageamento por Ressonância Magnética , Imagem Molecular
16.
Ann Clin Transl Neurol ; 11(1): 225-234, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37986706

RESUMO

INTRODUCTION: Ovarian teratoma is a common occurrence in patients with anti-NMDA receptor encephalitis (NMDARe), and its removal is crucial for a favorable prognosis. However, the initial pathogenesis of autoimmunity in the encephalitic teratoma remains unclear. In this study, we aimed to investigate the genomic landscape and microscopic findings by comparing NMDARe-associated teratomas and non-encephalitic control teratomas. MATERIALS AND METHODS: A prospective consecutive cohort of 84 patients with NMDARe was recruited from January 2014 to April 2020, and among them, patients who received teratoma removal surgery at Seoul National University Hospital were enrolled. We conducted a comparison of whole-exome sequencing data and pathologic findings between NMDARe-associated teratomas and control teratomas. RESULTS: We found 18 NMDARe-associated teratomas from 15 patients and compared them with 17 non-encephalitic control teratomas. Interestingly, the genomic analysis revealed no significant differences in mutations between encephalitic and non-encephalitic teratomas. Pathologic analysis showed no discrepancies in terms of the presence of neuronal tissue and lymphocytic infiltration between the encephalitic teratomas (n = 14) and non-encephalitic teratomas (n = 18). However, rituximab-naïve encephalitic teratomas exhibited a higher frequency of germinal center formation compared to non-encephalitic teratomas (80% vs. 16.7%, P = 0.017). Additionally, rituximab-treated encephalitic teratomas demonstrated a reduced number of CD20+ cells and germinal centers in comparison to rituximab-naïve encephalitic teratomas (P = 0.048 and 0.023, respectively). DISCUSSION: These results suggest that the initiation of immunopathogenesis in NMDARe-associated teratoma is not primarily attributed to intrinsic tumor mutations, but rather to immune factors present in the encephalitic patient group, ultimately leading to germinal center formation within the teratoma.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Neoplasias Ovarianas , Teratoma , Feminino , Humanos , Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Rituximab/uso terapêutico , Estudos Prospectivos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/epidemiologia , Teratoma/genética , Teratoma/complicações , Receptores de N-Metil-D-Aspartato , Genômica
17.
Arthritis Res Ther ; 26(1): 145, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080699

RESUMO

OBJECTIVES: Adipose tissue has been associated with knee osteoarthritis (KOA) pathogenesis, but the longitudinal changes in adipose tissue with KOA progression have not been carefully evaluated. This study aimed to determine if longitudinal changes of systemic and local adipose tissue is associated with radiographic progression of KOA. METHODS: This case-control study used data from the Osteoarthritis Initiative (OAI) and included 315 cases (all the right knees with a minimum of Kellgren-Lawrence score (KL) of 0 and an increase of ≥ 1 KL from baseline to 48 months) and 315 controls matched by age, sex, race, and baseline KL. Cross sectional area of IPFP (IPFP CSA) and subcutaneous adipose tissue around the distal thigh (SCATthigh) were measured using MRI images at baseline and 24 months. Conditional logistic regression models were fitted to estimate associations of obesity markers, IPFP CSA, and SCATthigh with radiographic KOA progression. Mediation analysis was used to assess whether IPFP CSA or SCATthigh mediates the relationships between baseline BMI and radiographic KOA progression. RESULTS: 24-month changes of IPFP CSA (ΔIPFP CSA) and SCATthigh (ΔSCATthigh) were significantly greater in cases compared to controls, whereas Δ BMI and Δ abdominal circumference were similar in both groups during follow-up. Adjusted ORs for radiographic KOA progression were 9.299, 95% CI (5.357-16.141) per 1 SD increase of Δ IPFP CSA and 1.646, 95% CI (1.288-2.103) per 1 SD increase of Δ SCATthigh. ΔIPFP CSA mediated the association between baseline BMI and radiographic KOA progression (87%). CONCLUSIONS: Subjects with radiographic progression of KOA, had significant increases in IPFP CSA and subcutaneous adipose tissue while BMI and abdominal circumference remained stable. Additional studies are needed to confirm these associations.


Assuntos
Tecido Adiposo , Progressão da Doença , Imageamento por Ressonância Magnética , Osteoartrite do Joelho , Gordura Subcutânea , Humanos , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Gordura Subcutânea/diagnóstico por imagem , Gordura Subcutânea/patologia , Estudos de Casos e Controles , Imageamento por Ressonância Magnética/métodos , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Radiografia/métodos , Estudos Longitudinais
18.
Exp Neurobiol ; 33(1): 1-17, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38471800

RESUMO

Autoimmune encephalitis (AIE) is a type of immunoreactive encephalitic disorder and is recognized as the most prevalent noninfectious encephalitis. Nevertheless, the rarity of definitive AIE diagnosis through biopsy or autopsy represents a significant hurdle to understanding and managing the disease. In this article, we present the pathological findings of AIE and review the literature based on a distinct case of AIE presenting as CD8+ T-lymphocyte predominant encephalitis. We describe the clinical progression, diagnostic imaging, laboratory data, and autopsy findings of an 80-year-old deceased male patient. The patient was diagnosed with pulmonary tuberculosis 6 months before death and received appropriate medications. A week before admission to the hospital, the patient manifested symptoms such as a tendency to sleep, decreased appetite, and confusion. Although the patient temporally improved with medication including correction of hyponatremia, the patient progressed rapidly and died in 6 weeks. The brain tissue revealed lymphocytic infiltration in the gray and white matter, leptomeninges, and perivascular infiltration with a predominance of CD8+ T lymphocytes, suggesting a case of AIE. There was no detectable evidence of viral infection or underlying neoplasm. The autopsy revealed that this patient also had Alzheimer's disease, atherosclerosis, arteriolosclerosis, and aging-related tau astrogliopathy. This report emphasizes the pivotal role of pathological examination in the diagnosis of AIE, especially when serological autoantibody testing is not available or when a patient is suspected of having multiple diseases.

19.
Adv Mater ; 36(2): e2307523, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37972308

RESUMO

The development of organic-based optoelectronic technologies for the indoor Internet of Things market, which relies on ambient energy sources, has increased, with organic photovoltaics (OPVs) and photodetectors (OPDs) considered promising candidates for sustainable indoor electronic devices. However, the manufacturing processes of standalone OPVs and OPDs can be complex and costly, resulting in high production costs and limited scalability, thus limiting their use in a wide range of indoor applications. This study uses a multi-component photoactive structure to develop a self-powering dual-functional sensory device with effective energy harvesting and sensing capabilities. The optimized device demonstrates improved free-charge generation yield by quantifying charge carrier dynamics, with a high output power density of over 81 and 76 µW cm-2 for rigid and flexible OPVs under indoor conditions (LED 1000 lx (5200 K)). Furthermore, a single-pixel image sensor is demonstrated as a feasible prototype for practical indoor operating in commercial settings by leveraging the excellent OPD performance with a linear dynamic range of over 130 dB in photovoltaic mode (no external bias). This apparatus with high-performance OPV-OPD characteristics provides a roadmap for further exploration of the potential, which can lead to synergistic effects for practical multifunctional applications in the real world by their mutual relevance.

20.
J Biol Chem ; 287(35): 29648-53, 2012 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-22807443

RESUMO

The heterodimeric Rag GTPases consisting of RagA (or RagB) and RagC (or RagD) are the key regulator activating the target of rapamycin complex 1 (TORC1) in response to the level of amino acids. The heterodimer between GTP-loaded RagA/B and GDP-loaded RagC/D is the most active form that binds Raptor and leads to the activation of TORC1. Here, we present the crystal structure of Gtr1p(GTP)-Gtr2p(GDP), the active yeast Rag GTPase heterodimer. The structure reveals that GTP-to-GDP conversion on Gtr2p results in a large conformational transition of this subunit, including a large scale rearrangement of a long segment whose corresponding region in RagA is involved in binding to Raptor. In addition, the two GTPase domains of the heterodimer are brought to contact with each other, but without causing any conformational change of the Gtr1p subunit. These features explain how the nucleotide-bound statuses of the two GTPases subunits switch the Raptor binding affinity on and off.


Assuntos
Guanosina Difosfato/química , Guanosina Trifosfato/química , Proteínas Monoméricas de Ligação ao GTP/química , Complexos Multienzimáticos/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimologia , Cristalografia por Raios X , Guanosina Difosfato/genética , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/genética , Guanosina Trifosfato/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Ligação Proteica , Estrutura Quaternária de Proteína , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
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